Method for improving fuel cell performance

• US 20010044040A1
• Filed: 05/22/2001
• Published: 11/22/2001
• Est. Priority Date: 05/22/2000
• Status: Active Grant

• Current Assignee: Los Alamos National Security LLC (Government of the United States of America)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Zawodzinski, Thomas, Uribe, Francisco A.
• Granted Patent: US 6,635,369 B2
• Time in Patent Office: Days
• US Class Current: 429/13
• CPC Class Codes: H01M 8/04238 Depolarisation
• CPC Class Codes: H01M 8/043 applied during specific periods
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A method is provided for operating a fuel cell at high voltage for sustained periods of time. The cathode is switched to an output load effective to reduce the cell voltage at a pulse width effective to reverse performance degradation from OH adsorption onto cathode catalyst surfaces. The voltage is stepped to a value of less than about 0.6 V to obtain the improved and sustained performance.

Claims

1. A method for operating a fuel cell at high voltage for sustained periods including the step of switching the cathode to an output load effective to reduce the cell voltage at a pulse width effective to reverse performance degradation from OH adsorption on cathode catalyst surfaces.

2. The method according to

claim 1

, where the cell voltage is reduced to a voltage less than 0.6 V.

3. The method according to

claim 1

, where the cell voltage is reduced to a voltage less than or equal to about 0.5 V.

4. The method according to

claim 1

, where the cell voltage is reduced over a pulse width equal to or greater than about 0.4 s.